The title compound, C14H10Cl2N2O·H2O, has a nearly planar extended conformation [C-N-N-C = -173.66 (15)°]. The dihedral angle between the aromatic rings is 4.6 (2)°. The water mol­ecules alternate with benzohydrazide mol­ecules in chains formed by O-HO hydrogen bonds which run parallel to the a axis. These chains are linked to neighboring chains through N-HO and C-HO inter­actions, forming a layer parallel to (001).

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